Trapped neutrophil syndrome in a young Border Collie dog: A new clinical presentation

An 11‐month‐old Border Collie dog presented with recurrent fever since the age of 3 months. Clinical examination revealed stunted growth, facial dysmorphism, fever, oral and third eyelid ulcerations and stiff gait with tarsal hyperlaxity. Clinicopathologic testing revealed neutropenia with normal neutrophil maturation in the bone marrow, ulcerative neutrophilic stomatitis and glossitis and a nonperforating duodenal ulcer. Genetic testing showed a mutation in the vacuolar protein sorting‐associated protein 13B gene, establishing a diagnosis of trapped neutrophil syndrome. Steroid therapy was not prescribed due to the presence of a duodenal ulcer. Two weeks later, antibiotics and omeprazole facilitated a mild clinical improvement with relapse; euthanasia was subsequently elected. This case highlights clinical signs not previously described in dogs but known in humans with Cohen syndrome, including buccal ulcerations or joint hyperlaxity. This is also the first description of this disease in France, where Border Collies are commonly bred.